Fix

src/main/java/refinedstorage/block/BlockGrid.java

@@ -61,9 +61,9 @@ public class BlockGrid extends BlockMachine {
     @Override
     public boolean onBlockActivated(World world, BlockPos pos, IBlockState state, EntityPlayer player, EnumHand hand, ItemStack heldItem, EnumFacing side, float hitX, float hitY, float hitZ) {
         if (!world.isRemote) {
-            ((TileGrid) world.getTileEntity(pos)).onGridOpened(player);
-
             player.openGui(RefinedStorage.INSTANCE, RefinedStorageGui.GRID, world, pos.getX(), pos.getY(), pos.getZ());
+
+            ((TileGrid) world.getTileEntity(pos)).onGridOpened(player);
         }
 
         return true;

src/main/java/refinedstorage/tile/controller/TileController.java

@@ -79,7 +79,6 @@ public class TileController extends TileBase implements IEnergyReceiver, ISynchr
     private int wirelessGridRange;
 
     private boolean couldRun;
-    private boolean syncing;
 
     private long lastEnergyUpdate;
 
@@ -310,8 +309,6 @@ public class TileController extends TileBase implements IEnergyReceiver, ISynchr
     }
 
     private void syncItems() {
-        this.syncing = true;
-
         itemGroups.clear();
 
         for (IStorage storage : storages) {
@@ -361,19 +358,15 @@ public class TileController extends TileBase implements IEnergyReceiver, ISynchr
         }
 
         itemGroups.removeAll(combinedGroups);
-
-        this.syncing = false;
     }
 
     public void syncItemsWithClients() {
-        if (!syncing) {
         for (EntityPlayer player : worldObj.playerEntities) {
-                if (player.openContainer.getClass() == ContainerGrid.class) {
+            if (player.openContainer.getClass() == ContainerGrid.class && pos.equals(((ContainerGrid) player.openContainer).getGrid().getControllerPos())) {
                 syncItemsWithClient((EntityPlayerMP) player);
             }
         }
     }
-    }
 
     public void syncItemsWithClient(EntityPlayerMP player) {
         RefinedStorage.NETWORK.sendTo(new MessageGridItems(this), player);

src/main/java/refinedstorage/tile/grid/IGrid.java

@@ -1,5 +1,6 @@
 package refinedstorage.tile.grid;
 
+import net.minecraft.util.math.BlockPos;
 import refinedstorage.block.EnumGridType;
 import refinedstorage.storage.ItemGroup;
 import refinedstorage.tile.config.IRedstoneModeConfig;
@@ -13,6 +14,8 @@ public interface IGrid {
 
     void setItemGroups(List<ItemGroup> groups);
 
+    BlockPos getControllerPos();
+
     void onItemPush(int playerSlot, boolean one);
 
     void onItemPull(int id, int flags);

src/main/java/refinedstorage/tile/grid/TileGrid.java

@@ -7,6 +7,7 @@ import net.minecraft.inventory.*;
 import net.minecraft.item.ItemStack;
 import net.minecraft.item.crafting.CraftingManager;
 import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.util.math.BlockPos;
 import net.minecraftforge.items.IItemHandler;
 import net.minecraftforge.items.wrapper.InvWrapper;
 import refinedstorage.RefinedStorage;
@@ -97,6 +98,11 @@ public class TileGrid extends TileMachine implements IGrid {
         this.itemGroups = itemGroups;
     }
 
+    @Override
+    public BlockPos getControllerPos() {
+        return controller != null ? controller.getPos() : null;
+    }
+
     public void onGridOpened(EntityPlayer player) {
         if (isConnected()) {
             controller.syncItemsWithClient((EntityPlayerMP) player);

src/main/java/refinedstorage/tile/grid/WirelessGrid.java

@@ -21,8 +21,8 @@ import java.util.ArrayList;
 import java.util.List;
 
 public class WirelessGrid implements IGrid {
-    private ItemStack stack;
     private EnumHand hand;
+    private BlockPos controllerPos;
     private int sortingType;
     private int sortingDirection;
     private int searchBoxMode;
@@ -30,8 +30,8 @@ public class WirelessGrid implements IGrid {
     private long lastUpdate;
 
     public WirelessGrid(ItemStack stack, EnumHand hand) {
-        this.stack = stack;
         this.hand = hand;
+        this.controllerPos = new BlockPos(ItemWirelessGrid.getX(stack), ItemWirelessGrid.getY(stack), ItemWirelessGrid.getZ(stack));
         this.sortingType = ItemWirelessGrid.getSortingType(stack);
         this.sortingDirection = ItemWirelessGrid.getSortingDirection(stack);
         this.searchBoxMode = ItemWirelessGrid.getSearchBoxMode(stack);
@@ -53,18 +53,23 @@ public class WirelessGrid implements IGrid {
         this.lastUpdate = System.currentTimeMillis();
     }
 
+    @Override
+    public BlockPos getControllerPos() {
+        return controllerPos;
+    }
+
     @Override
     public void onItemPush(int playerSlot, boolean one) {
-        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridStoragePush(ItemWirelessGrid.getX(stack), ItemWirelessGrid.getY(stack), ItemWirelessGrid.getZ(stack), playerSlot, one));
+        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridStoragePush(controllerPos.getX(), controllerPos.getY(), controllerPos.getZ(), playerSlot, one));
     }
 
     @Override
     public void onItemPull(int id, int flags) {
-        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridStoragePull(ItemWirelessGrid.getX(stack), ItemWirelessGrid.getY(stack), ItemWirelessGrid.getZ(stack), id, flags));
+        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridStoragePull(controllerPos.getX(), controllerPos.getY(), controllerPos.getZ(), id, flags));
     }
 
     public void onClose(EntityPlayer player) {
-        TileEntity tile = player.worldObj.getTileEntity(new BlockPos(ItemWirelessGrid.getX(stack), ItemWirelessGrid.getY(stack), ItemWirelessGrid.getZ(stack)));
+        TileEntity tile = player.worldObj.getTileEntity(controllerPos);
 
         if (tile instanceof TileController) {
             ((TileController) tile).getWirelessGridHandler().handleClose(player);
@@ -109,7 +114,7 @@ public class WirelessGrid implements IGrid {
 
     @Override
     public void onCraftingRequested(int id, int quantity) {
-        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridCraftingStart(ItemWirelessGrid.getX(stack), ItemWirelessGrid.getY(stack), ItemWirelessGrid.getZ(stack), id, quantity));
+        RefinedStorage.NETWORK.sendToServer(new MessageWirelessGridCraftingStart(controllerPos.getX(), controllerPos.getY(), controllerPos.getZ(), id, quantity));
     }
 
     @Override